Design and fabrication of

prototype pulse jet engine

Joel kevin saldanhaVikram mallyaNiyanth yadav

Hencil mendonca

What is Project Pulse–Jet?

▫Project Pulse – Jet is an analytical study of how a pulse-jet engine works.

▫Our Goals To design, build pulse-jet engine.

▫Plan of Action Research and design a prototype of a pulse-jet

engine. Build the prototype based on our design.

History of the pulsejet• The pulsejet engine was first invented in the early 1900 by a Swedish

inventor Martin Wiberg

• Paul Schmidt, who engineered the first production pulsejet during the Second World War with his flying bomb, the Argus V1. ▫ Nicknamed the “buzz” bomb because of the low hum it admitted during

flight.▫ Used by the Germans to bomb London from 1944-1945▫ Over 9,000 V-1 were fired on England during WW2

• The pulsejet took a backseat in the engineering world when the turbofan jet engine was invented

• Has returned to the engineering scene as of late because of the interest in Pulse Detonation Engines (PDE).

How does it work?

• A pulsejet engine is a very simple jet engine consisting of very little to no moving parts. The combustion cycle comprises five or six phases: Induction, Compression, (in some engines) Fuel Injection, Ignition, Combustion, and Exhaust.

• The rapidly expanding gasses exit out of the engine and as this happens a vacuum is created in the combustion chamber which pulls in a fresh new air charge fro m the atmosphere, and then the whole cycle repeats itself.

Combustion Cycle

Types of Pulse Jets• There are two basic types of pulsejets.

▫ valve or traditional pulsejet ▫ valve-less pulsejet.

Design Research

• The Lenoir cycle is an idealized thermodynamic cycle often used to model a pulse-jet engine.

• Comprises of 3 cycles:▫ Heat added at constant

volume.▫ Adiabatic Expansion.▫ Exhaust of the hot gasses at a

constant pressure.• Thrust can be directly calibrated on

the basis that the cycle is completed over two

working strokes.

Design Research• C.E. Tharratt

▫Discovered a surprising result that the ratio of duct volume to effective length had a linear relationship to the maximum static thrust or: V/L = 0.00316F

▫This relationship has been compared to all known pulse-jets from the large V-1 “flying bomb” of over 500 lb. thrust to the miniature Dyna-jets of 4-5 lbs. thrust.

Thrust = 2.2 x Cross-Sectional area or F = 2.2A

Valveless Pulse-Jet plan design

Material used

Fuel and Fuel delivery

• Fuel▫ LPG

Easily obtained. Boiling Point below room temperature. Being a gas allows for easier starting.

• Fuel Delivery System▫ LPG TANK▫ Gas Fitting Nozzle▫ Needle Valve

Building and Testing•Materials

▫Pulse-Jets Main body. Rolled and seem welded using 0.063”

MILD Steel Sheet Metal.

Testing

•Prototype will be tested to verify thrust output.

•Test Stand will be constructed to secure Pulse-Jet safely.

Budget •MILD steel sheet metal, with labor: Rs

5400

•Lpg Tank: Rs o, on hand•Fuel Delivery System: on hand•Test stand material: Rs 2000•Fuel: Rs 600• •Total: Rs 8000

Project’s Future •Continue testing on prototype to gain

further knowledge of its operating cycle.

•Construct larger Jet using the knowledge gained from this smaller prototype.

•Use larger engine to power to propel a manned vehicle.

Bibliography

•Simpson Bruce “The Enthusiasts' Guide to Pulsejet Engines”

•http://www.aardvark.co.nz/pjet/•http://www.zachmiers.com/

pulsejetbook/•http://www.pulse-jets.com/•Roy, Gabriel “Combustion

processes in propulsion control, noise, and pulse detonation”

Questions?